is there anyway to tell if a tpi engine is a 305 or a 350 just looking at it?? such as the distributer, i was told only the 305s had an internal coil and the 5.7s had an external, i was also told that only the 5.7s had the duel fan setup, if it helps i have a picture of the engine, and the vin says it came with a 305tpi.

this one has the duel fans, an, auto trans, external coil.

on a side not i was told the duel fans came on ac cars from someone else.

 

No, there are no visual ways to tell a 305 from a 350, apart from checking the casting numbers on the block.

 

The dual fans is not a clue. My 90 IROC was a 305 TPI and it had dual fans. Try getting a part number off of the spark control module or knock sensor and run it at GM parts direct. Those parts are have specific numbers for 305s and specific numbers for 350s. I found the follow part numbers for a 350 over on the TBI boards. They should still apply:


ESC Moudle: GM p/n 16126761
Knoc Sensor: GM p/n 10456288

Hope this helps.

 

hmm, yea, im thinking its a 305, thanks for the help guys!

 

Look at the vin number. If the 8th digit is F than its a 305, if its 8 than its 350. I think.
Look at it its right no the dash.

 

"is there anyway to tell if a tpi engine is a 305 or a 350 just looking at it?? such as the distributer, i was told only the 305s had an internal coil and the 5.7s had an external, i was also told that only the 5.7s had the duel fan setup, if it helps i have a picture of the engine, and the vin says it came with a 305tpi."

 

If the VIN says it's a 305, I would bet it's a 305. People generally try to claim a 305 as a 350 but never the othe way around (except maybe at the track).

But as Aperion said, other than the casting number (and the vin#) there is no visual way to distinguish the two without physically removing the heads and measuring the bore.

There is a 5.0 and 5.7 that is casted into the side of the block. And, if you are sure the heads have never been swapped, you could use the casting number of the heads.

If you pulled the ECM and got the "Broadcast Code" of the memcal, it can be checked to tell you if it came from a 305 or a 350. But that can be changed, so that doesn't guarantee that you have an original 350 or 305.

If it's a 5 speed then it is a 305.

 

Block casting numbers, people!! That's it. The only way. VIN and head castings don't tell you anything. The motor could have been changed at any time.

BTW and you would have already known this.

I'd say there's a good 50/50 shot that this is a 350

 

why would you say there is a 50/50 shot? the vin # says its a 305, id say there is a small chance its a 350.

 

You never can be sure unless you dig deep enough. I've got a 305 in my garage that the guy swore was a 350 rebuilt and that it may even of had a stroker kit put in. It didin't cost me anything ( a friend bought it for the tpi)and when the motor was pulled, surprise! it's a lowly 150hp 305.

 

We all said that to start (if you read all of our posts).

We offered "logical reasons and tests" to confirm it's STILL a 305. If the motor had a slightest chance of being CHANGED to a 350, people would be saying it 350 (not a 305). This is a case where everything is pointing to a 305 and the new owner still wonders if it MIGHT be a 350.

Chances are 99.99999999% its a 305.